Update, February 12, 9 a.m.: Crown Princess departed Port Everglades Saturday afternoon after a two-day intensive cleaning. According to the CDC Web site, 288 passengers (9.36 percent out of 3,078) and 68 crew (5.77 percent of 1,178) reported gastrointestinal illness during the shortened cruise.

(February 7, 1:15 p.m. EST) -- Crown Princess will end its current cruise two days early following a spike in cases of gastrointestinal illness for the second straight week.

In a statement, Princess Cruises said the 113,000-ton, 3,080-passenger ship will return to its Fort Lauderdale homeport on Thursday instead of Saturday, where it will undergo two days of sanitization in consultation with the U.S. Centers for Disease Control and Prevention (CDC).

At last count, 114 passengers (3.7 percent out of 3,078) and 59 crew (5 percent of 1,178) on the weeklong Southern Caribbean cruise have reported a gastrointestinal illness believed to be Norovirus, said the line.

Impacted passengers will receive full refunds for the cruise, flights home, coverage of change fees if air was not booked through Princess, hotel accommodation if necessary and a 25 percent future cruise credit.

A total of 364 of 3,103 passengers and 30 of 1,168 crew were infected on last week's cruise, after which Princess undertook what it describes as "rigorous sanitization measures ... [including] a comprehensive disinfection of all cabins and public areas." The sanitization, which delayed the ship's February 4 departure by some six hours, was overseen by the CDC together with the line's public health, medical and onboard departments.

Norovirus is the second most common illness next to the common cold, and is highly contagious, spreading easily in confined spaces like hospitals, hotels, dormitories and cruise ships. Symptoms include vomiting and diarrhea, and millions are infected each year.

Cruise lines participating in the CDC's Vessel Sanitation Program -- and every major operator does -- are required to report the total number of GI cases evaluated by the medical staff before the ship arrives at a U.S. port when sailing from a foreign port. A separate notification is required when the count exceeds 2 percent of the total number of passengers or crew onboard.

Princess said the upcoming two-day disinfection will include "bringing aboard additional cleaning crew to assist with a thorough sanitization of all public spaces and surfaces including soft furnishing and carpets, railings, door handles and the like. Additionally, once all of the passengers have disembarked on Thursday morning, all bed linens and towels will be removed from every stateroom. The staterooms will be sanitized multiple times before making up the rooms with fresh linens and towels on Saturday morning, just prior to passenger embarkation."

The line said it expects the next cruise to depart on February 11 as scheduled.

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--by Dan Askin, News Editor